Electrical call-box



(No Model.)

G. P. GALE.

ELEGTRIGAL CALL BOX.

No. 431,141. P11611161 July 1, 18901 i UNITED STATES PATENT OFFICE.

GEORGE F. GALE, OF W'INTHROP, ASSlGNOR OF ONE-HALF TO ARNOLD l3. HOLMES, OF BOSTON, MASSACHUSETTS.

ELECTRICAL CALL-BOX.

SPECIFICATION forming part of Letters Patent No. 431,141, dated July 1. 1890. Application filed February 2'7, 1890. Serial No. 341,950. (No model.')

To all whom it may concern.-

Be it known that I, GEORGE F. GALE, of Winthrop, in the county of Suffolk, State of Massachusetts, have invented certain new and 5 useful Improvements in Electrical Gall-Boxes,

of which the following is a description sufficiently full, clear, and exact to enable any person skilled in the art or science to which said invention appertains to make and use the same, reference being had to the accompanying drawings, forming part of this specification, in which box.

Fig. 2 is a side elevation of the same;

Fig. 3, a front elevation of the box, the face being removed to show the interior mechanism; and Fig. 4'. an edge elevation, partly in section, on line 68 a: in Fig.

Like letters and figures of reference indicate corresponding parts in the different figures of the drawings.

My invention relates especially to an improved escapement mechanism for electric messenger call-boxes; and it consists in certain novel features, hereinafter fully set forth and claimed, the object being to produce a simpler, cheaper, and more effective device of this character than is now in ordinary use.

The nature and operation of the improvement will be readily understood by all conversant with such matters from the following explanation.

In the drawings, A represents the back plate of the box,which is provided with flanges h, in which are formed screwl1oles (Z for attaching it to the wall.

Guards f prevent the plates from coming directly into contact with said wall. AV-shaped frame g is secured by screws 71 to the face of the plate A. A horizontal shaftiisjournaled in the apex of said,

frame and plate. A crank-handle j is secured to the outer end of said shaft, said handle being disposed outside the case by which the mechanism shown is covered.

A large gear said back plate.

Said spring acts torsionally to return the shaft after having been rotated by the crank. Series of openings I m p are formed in the body of the gear and openings correspondingin number with the number of I the call-box. A post q passes through the back plate and is insulated therefrom by rubber disks 1' t. A nut and plate 3 c on said post atthe rear of said back plate form a connector for a wire of the electric circuit, the opposite pole-wire being connect-ed directly to the plate A. A vertical brush w is secured to the post q, said brush having two arms 3 z in engagement with the faceof the gear B, the brush-arm zbeing disposed so that its free end will enter the openings Imp as the gear is rotated. Adisk 15 of insulating material is disposed loosely on the shaft 2' between the frame g and gear 13, and is provided with a radial arm' 16 in position to pass under and disengage the brush-arm y from the face of the gear when the disk is rotated. The tension of the spring it forces a stop 17 on the gear against said disk-arm and tends to hold it out of contact with the brush-arm, a similar stop 18 on the arm 16 at the same time engaging a boss 19 on the frame g, and prevents the disk from being rotated too far by the spring. A vertical lever 20 is pivoted at 21 by its lower end to the plate A. A stop 22 on said plate restricts the movement of said lever in one direction. A laterally-projecting pin 23 is secured to said lever, and a loose pinion 24 is disposed thereon, said pinion meshing with the gear B. On the outer end of said pin a V-toothed ratchet 25 is mounted, a four-arm spring 26 on said pin bearing against the outer face of said ratchet. The tension of said spring is adjusted by means of a nut 27, turned onto the outer end of the pin.

A pawl D is pivoted to the back plate A in the same plane as the ratchet 25, and has a rectangular groove 28 in its edge forming two parallel teeth 29, adapted to engage the ratchet-teeth and restrain the movement of said ratchet. An adj listing-screw 30 passes through the free end of the lever 20 into engagement with the pivot of the pawl D, the purpose of said screw being to regulate the right-to-left movement of said lever.

In the use of my improvement, the crank [00 j being turned from left to right, the gear B is moved in a corresponding. direction. Both arms of the brush to being in contact with the gear, a closed circuit is sustained. As the last of the openings 19 passes under the brusharm 2, a stud 33 on the face of the gear engages the disk-arm 16 on the left, as viewed in Fig. 3, forcing said arm under the brusharm y and disengaging it from contact with the gear, the arm 2, however, continuing in contact therewith. As soon as the crank is released the spring 7c, wound by the rotation of the shaft 1', causes it to rotate in the opposite direction. The slots 13 m Z passing consecutively under the brush-arm 2', each breaks the electric circuit and indicates thereby at the central offiee the number of the box in the usual manner. The arm 16 of the insulatingdisk is stationary under the brush-arm until the last opening Z has passed the brush-arm 2, when the stop 17 on the gear engages said insulator and moves it out of contact with said brush until its stop 18 meets the frame 9, stopping the mechanism. A plate 35 on the post q, bearing against the brush, regulates the pressure of its arm 2 on the gear, so that there shall be an absolute break of its contact with said gear when the openings Z mp pass thereunder. The point of the brusharm is V-shaped in side elevation (see Fig. 4) to better effect this. As the crank is 0perated to rotate the gear, as described, the lever 20 is carried thereby from left to right untilit meets the stop 22. The tension-spring 26 jams the ratchet 25 sufficiently hard against the pinion 24. to prevent said pinion rotatingand traveling on the gear until said lever on which the pinion is journaled meets the stop 22. Upon the return of the gear B, by means of the spring 75, the lever 20 is thrown back again from right to left, its screw 30 meeting the pawl-pivot and the ratchet 25 at the same time engaging the teeth of said pawl, which acts as a doubletoothed click to retard the motion of the gear-train. By thus pivoting the escapement mechanism so that the click and ratchet are out of contaetdu ring the winding of the spring one-half. of the wear upon the ratchet-teeth is avoided. Moreover, ratchets with teeth out with far less accuracy may be employed than when the ordinary pawl is used, and much less care is necessary in the adjustment of the parts. The wear of the ratchet-teeth may be compensated for byv turning out the screw 30 and permitting the gear to throw said ratchet so much nearer the click.

The construction of the device is greatly lessened in cost by the use of my improved escapement, the necessity of employing spring-pawls and similar expensive parts being done away with.

Having thus explained my invention, what I claim is- 1. In an escapement mechanism, the combination of a double-toothed click pivoted to a fixed plate or support,a reciprocating main gear, a pivoted lever, a ratchet and pinion journaled on said lever, said pinion meshing with the gear and said ratchet being disposed in position to engage the click when the gear reciprocates, substantially as set forth.

2. An escapement mechanism comprising the pivoted lever 20, bearing the pinion 24 and ratchet 25, said pinion meshing with a reciprocating gear, stops for the lever, the tension-spring 26, and click D, combined substantially as described.

3. In an escapement mechanism, the reciprocating gear B, combined with the pivoted lever 20, bearing a ratchet and pinion meshing with said gear, an adjustable stop carried by the lever, and a double-toothed click in position to engage said ratchet, substantially as described.

4. In a call-box, the combination of a back plate, a spring-reciprocated indicating-gear, a two-arm brush in contact therewith, anoinsulating-plate on the gear-shaft adapted to engage a brush-arm, stops on the gear and plate for determining their rotation, and an escapement comprising a double toothed click and a pinion and ratchet mounted on a pivoted support, said pinion meshing with the gear, substantially as and for the purpose set forth.

5. In a signal or call box, a reciprocating gear having indicating-slots in one-half or less of its surface, a two-arm contact-brush, one arm thereof being placed to enter said slots and the companion arm normally in contact with the surface of the gear, and an insulating-plate on the gear-shaft for breaking the contact of said arm until the companion arm passes said slots, substantially as described.

GEORGE F. GALE.

Vitnesses:

O. M. SHAW, K. DURFEE. 

